1. Field of the Invention
The present invention relates generally to an organic light emitting diode (OLED) display and a method of manufacturing the same, and more particularly, to an organic light emitting diode display with a pad and a manufacturing method thereof.
2. Description of the Related Art
Generally, an organic light emitting diode display includes a thin film transistor, an anode and a cathode facing each other, and an organic emissive layer disposed between the anode and the cathode.
An organic light emitting diode display where the thin film transistor has source and drain electrodes, and the drain electrode of the thin film transistor is integrally formed with the anode in a body, has been recently developed. With such an organic light emitting diode display, a pad, which is disposed at a pad area neighboring the display area with the organic emissive layer and exposed to the outside, is formed with substantially the same material as the anode. That is, the drain electrode, the anode, and the pad are formed with substantially the same material.
Meanwhile, the organic light emitting diode displays are classified into a front emission type, a rear emission type, and a one panel dual emission type, depending upon the light emitting direction thereof. Among them, the front emission type is advantageous in the aspect of optical aperture ratio, and the anode should contain a high reflective metal in order to construct a front emission type of organic light emitting diode display.
However, with the organic light emitting diode display where the drain electrode, the anode, and the pad are formed with substantially the same material, if the anode contains an easily oxidizable metal with high reflectivity and low electrical resistivity such as silver (Ag), the pad exposed to the outside also contains such an easily oxidizable metal so that it is liable to be oxidized.
The above information disclosed in this Background section is only for enhancement of understanding of the background of the described technology and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.